[cc65] FAR handling?

Hi Uz,

What is the current state of 24 bit address handling in CC65?
Is it just some thing that can be utilized at an assembler level?

I'm wondering how, in a 'C' source file, to declare an external 
function. Should there be a wrapper to indicate the segment?
Would the import (from the example below) be expected to look 
something like:

	.import		_far_func: far

The docs begin to go into subjects like 'choosing the memory model'
but this doesn't appear complete?

I think this would be a good area to push development against as 
many of the targets (e.g. Atari, Lynx, NES) are using bank switching
models for cartridge development and this could aid us immensely.
I think previous discussion halted on trying to decide methods by
which different platforms would handle the bank selection? This
could get tricky, but perhaps these could get passed to a user 
provided macro or 'jump to' code that will perform the bank 
selection and call, e.g. replacing the statement: 

	jsr     _far_func

To all: What other thoughts have people had regarding this?
e.g. would we want a stack to push/pop current bank to, so that
a 'far' function wouldn't end with RTS but another macro or jump
to handle the return correctly?

I note too that the Atari has no "Extended memory drivers".
Perhaps these could be implemented instead?

Kind regards,
Mark

'C' :-

extern int __far__ far_func(void);

int local_func(char a)
{
	return 2*a;
}

int main(int argc, char *argv[])
{
	return (local_func(far_func()));
}

'ASM' :-

;
; File generated by cc65 v 2.10.1
;
	.fopt		compiler,"cc65 v 2.10.1"
	.setcpu		"6502"
	.smart		on
	.autoimport	on
	.case		on
	.debuginfo	off
	.importzp	sp, sreg, regsave, regbank, tmp1, ptr1, ptr2
	.macpack	longbranch
	.import		_far_func
	.export		_local_func
	.export		_main

; ---------------------------------------------------------------
; int __near__ local_func (unsigned char)
; ---------------------------------------------------------------

.segment	"CODE"

.proc	_local_func: near

.segment	"CODE"

	ldx     #$00
	lda     #$02
	jsr     pushax
	ldy     #$02
	ldx     #$00
	lda     (sp),y
	jsr     tosumulax
	jmp     L0002
L0002:	jsr     incsp1
	rts

.endproc

; ---------------------------------------------------------------
; int __near__ main (int, unsigned char**)
; ---------------------------------------------------------------

.segment	"CODE"

.proc	_main: near

	.forceimport	initmainargs

.segment	"CODE"

	jsr     _far_func
	jsr     pusha
	jsr     _local_func
	jmp     L0004
L0004:	jsr     incsp4
	rts

.endproc

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